Gly 4 Plus has killed everything I have sprayed it with including poison ivy, sumac, and oak around trees and really put a hurt on the briars, it did not kill the briars out but it stopped all growth and dried them up for a string weed-eater to take them out no problem. Now I mix it stronger than the instructions, I buy it in the 2.5 gal jugs and mix 20 ounces of Gly 4 Plus with 15 gallons of water, which I think the instructions say 3/4 ounce per gallon. Gly Star also seems to work however it takes twice as long for some reason to work and show results.